Night vision is the ability to
see in low light conditions.
Humans have poor night vision
compared to many animals, in
part because the human eye
lacks a tapetum lacidum. Night
glasses are telescopes or
binoculars with a large
diameter objective. Large
lenses can gather and
concentrate light, thus
intensifying light with purely
optical means and enabling the
user to see better in the dark
than with the naked eye alone.
Night vision binoculars are
most often used by the
military and law enforcement
agencies, but are available to
civilian users. First
generation night vision
goggles, introduced during the
Vietnam War, were an
adaptation of earlier active
GEN 0 technologies, and rely
on ambient light instead of an
infrared light source. Using
an S-20 photocathode, their
image intensifiers produce a
light amplification of around
1000 X, but are quite bulky
and require moonlight to
function properly. For the spy
in all of us, armyuniverse
provides you with a variety of
GEN 1 night vision goggles.